Pulp-classifier.



R. D. JACKSON.

PULP C'LASSIFIER. APPLICATION FILED MAYZfi. I917.

1,316,038. PatentedSept. 16,1919.

INVENTOI? 5. D. JAG (5O W/T/VESS HIS A HORNE ROBERT D. JACKSON, 0]? SANFRANCISCO, CALIFORNIA.

PULP-CLASSIFIEB.

Application filed May 26, 1

To all whom it may concern Be it known that I, ROBERT D. JACKSON, acitizen of the United States, and a resident of the city and county ofSan Francisco and State of California, have invented certain new anduseful Pulp Classifiers, of which the following is a specification.

The invention relates to classifiers for separating particles ofmaterial of difierent sizes and is particularly adapted to be used inmetallurgical operations for classifying pulp or for separating sandsfrom slimes.

An object classifier in pulp settle directly on a conveyer by which theyare removed from the settling tank.

Another object of the invention is to. provide a classifier in which aplurality of classifications may be accomplished atone time. p

A further object of the invention is to of the invention is to provide aprovide a classifier which is adjustable to produce a givenclassificatlon for variations in the feed.

The invention possesses other advantageous features, some of which, withthe foregoing, will be set forth at length in the fol lowing descriptionwhere I shall outline in full that form of the invention which I haveselected for illustration in the drawings accompanying and forming partof the present specification. In said drawings I have shown one specificform .of my invention, but it is to be understood that I do not limitmyself to such form, since the invention as expressed in the claims maybe embodied in a plurality of forms.

Referring to said drawings:

Figure 1 is a top or plan view of one form of classifier of myinvention.

Fig. 2 is a longitudinal vertical section of the classifier shown inFig. 1.

Fig. 3 is a perspective view of a fragment of the conveyer.

In the classifier of my invention I employ a movable conveyer upon whichthejoversize or heavier particles settle directly and by which theytank. The smaller particles or fines are carried out by the current ofwater or solution.

The classifying current flows transversely of or across'the conveyer sothat the oversize particles thereon aregraded into difierent sizes andmeans are provided for removing Specification of Letters Patent. I

which the larger particles of the .the sprockets 15 and are carried fromthe settling Patented Sept. 16, 1919.

917. Serial no. 171,165.

and maintaining the separation of these grades.

The classifier of my invention comprises a tank 3 into which the pulp orother material to be classified, is fed. Arranged in the tank above thebottom 4 is an endless conveyer 5 which moves longitudinally of the tankand which is substantially as wide as the tank. The conveyer consistspreferably of a belt 6, supported at the edges and driven by chains 7,which engage in suitable sprockets 8 and 9 at the opposite ends of its,run, sprockets 8 preferably serving as the driving sprockets and beingustable, so that the tension on the chains may be varied. The lower runof the belt is held taut and prevented from slapping by the sprockets 12and the holding-down idler drum 13. A portion 14 of the upper runconveyer is arranged horizon.

tally and is maintained in that position by the supporting drum 16, andthe remainder of fhe upper run is inclined upwardly to the sprockets 8,this inclined portion extending above the level of the liquid in thetank and preferably over the edge of the tank. Secured to the belt are aplurality of transversely disposed buckets 17 preferably formed of sheetmetal bent into an angle shape and closed on the ends. The buckets areprovided at the lower portion of their upstanding walls with a pluralityof small holes 18 through which the liquid drains from the buckets asthey move up along the inclined path of the conveyer. These holes alsoserve to release the air from the buckets after they enter the solutionon the lower run of the conveyer.

The material to be classified flows from the launder 19 onto thespreading board 21 and thence into the tank. The liquid carrying thefines passes over the discharge apron 22. The spreading board isarranged at one side of the tank and, the discharge board at theopposite side, so that the classifying current travels transversely ofthe conveyer, and the horizontal portion ll of the conveyer is arrangedwithin the zone defined by the width of the spreading board or thedischarge apron, so that the distance between the surface of the liquidand the underlying conve er is the same at all points in the classi yingcurrent. This arrangement insures similar classification at all pointsin a strip taken longitudinally of the conveyer.

Since the classifying current flows transversely of the conveyer, agraded classification of the. material is produced, the larger andheavier particles depositing along the edge of the conveyer adjacent thefeed side of the tank and the successively number of hoppers may be usedand any desired grading .ma beobtained. When a definitefgra'd sdesirable, I prefer to divide the conveyer surface longitudinally intofixed zones by ridges 29, but these may be omitted, when desired.

Arranged adjacent the spreading board 21 and extending below the levelof the liquid in the tank is a diving board 31 under which all of thepulp fed into the tank must pass, thereby insuring submergence of all ofthe particles and preventing a surface' velocity of the current which isin excess of its normal velocity. In order to cause all of the settlingmaterial to fall onto the conveyer and to pervent it from passing intothe bottom of the tank, through the spaces between the conveyer and thesides of the tank, I arrange the deflecting aprons 32 along the sides ofthe tank directly above the chains and the deflecting apron 33 along theedge of the tank directly over the sprockets 9.

In order to insure the same classification of the material regardless ofthe quantity of the feed, or to vary the classification whilemaintaining the same feed, I have provided means for varying the widthof the classifying current so that with a varying feed its speed may bemaintained constant or with a constant feed, its speed may be varied.Mounted on the frame of the tank and depending into the liquid thereinand extending to adjacent the conveyer are movable channel boards 34;,between which the classifying current passes from the spreading board tothe discharge apron. These channel boards are supported on beams, theends of which rest on shelves on the sides of the tank, so that thechannel boards are readily movable longitudinally of the tank to varythe width of the classifying current, whereby the density of the pulpmay be kept constant with a different feed. Deflecting blocks 35 arearranged on the spreading broad to direct the incoming pulp between thechannel boards and these blocks are slid-able over the spreading board,so that the width of the feed stream may be readily varied.

2. In a pulp classifier, a settling tank adapted to receive the pulp tobe classified,

an imperforate conveyer of substantially the same width as said tankarranged to move longitudinally in said tank, and having a horizontalportion, deflecting aprons overlying the edges of said horizontalportion, a feed inlet arranged at one longitudinal sideof the tank overthe horizontal portion and a discharge outlet arranged on thle otherside of the tank opposite the feed in et.

. 3. In a classifier, a settling tank adapted to receive the material tobe classified, a horizontal movable conveyer in said tank arranged todirectly receive the settled material, means for producing a classifyingcurrent across said tank and means for confining said' current above thehorizontal conveyer.

4. In a classifier, a settling tank adapted to receive the material tobe classified, a flat horizontally disposed conveyer arranged tomovelongitudinally in said tank, a feed inlet at one longitudinal side ofthe tank, a discharge outlet at the opposite side and channel boardsextending across the tank for directing the current of material directlyacross the tank.

5. In a classifier, a settling tank adapted to receive the materlal tobe classified, a conveyer arranged to. move longitudinally in said tank,a feed inlet at one longitudinal side of the tank, a discharge outlet atthe opposite side, and channel boards movable longitudinally versely ofthe tank adapted to be moved classifying current.

6. In a classifier, a settling tank adapted to receive the material tobe classified, a conveyer arranged to move longitudinally in above theconveyer and to vary the width of the said tank, a feed inlet at onelongitudinal side of the tank, a discharge outlet at the opposite side,channel boards movable longitudinally of the tank arranged transverselyvof the tank, and means for directing the material from the feed inletbetween said channel boards.

7. In a classifier, a. settling tank adapted to receive the material tobe classified, a conveyer arranged to move longitudinally in said tankand having a horizontal portion, a feed spreading board arranged at oneof the tank arranged translongitudinal side of the tank, a dischargeapron arranged at the opposite side of the tank, and channel boards forconfining the cross current above the horizontal portion of theconveyer.

S. In a classifier, a settling tank adapted to receive the material tobe classified, a conveyer arranged to move longitudinally in said tank,a feed spreading'board arranged at one longitudinal side of the tank, adischarge apron arrangedat the opposite side of the tank, movablechannel boards arranged across the tank between the spreading board andthe discharge apron and adjustable means for varying the effective widthof the spreading board so that the material is introduced between saidchannel boards.

9. In a classifier, a settling tank adapted to receive the material tobe classified, a conveyer arranged to move longitudinally in said tankand to directly receive the settled material and deflecting apronssecured to the sides of the tank: above the conveyer and overlying the,edges thereof.

In testimony whereof, I have hereunto set my hand at San Francisco,California, this 18th day of May 1917.

In presence of- H. G; FROM.

